A variety of methods have been developed to remove thrombi and other unwanted material from a patient's vasculature. Examples include thrombolytic medications and mechanical devices such as fluid jets, ultrasound, laser, thermal, suction, balloons, rotating burrs, cutters, baskets, and wires. Thrombolytic medications are simpler to administer and have advantages in reaching any desired vessel, but disadvantages in slower action, monitoring requirements, bleeding complications, high cost, inability to remove harder or more organized thrombi, and travel to other vessels besides the target vessel. Mechanical devices are often faster and are specific to the target vessel, but have disadvantages in being larger size, difficulty in reaching a target vessel, local injury to the vessel wall, mechanical plugging, complicated and time-consuming setup, complicated operation requiring operator training and skill, and high cost; the effectiveness on harder or more organized thrombi varies, with the more effective devices being more invasive, more dangerous, or more expensive.
There are many situations in which it is desirable to remove thrombus or blood clots from the body, particularly in large blood vessels, heart chambers, or in extravascular spaces which could fill with blood during hemorrhage such as retroperitoneal bleeding, or other spaces such as cerebrospinal fluid spaces, hollow body organs, and so forth.
Existing thrombectomy devices, including fluid jet thrombectomy devices, have difficulty in treating large thrombi and in efficiently and effectively removing thrombus from large diameter vessels. A fluid jet catheter may obtain some mixing and work at some distance, but doing so safely and capturing all the thrombus for removal is problematic. A variety of thrombus removal catheters can be utilized in smaller vessels such as coronary or leg arteries, and so forth.
Thus, a need remains for improved thrombus removal capability particularly for large vessels, including peripheral or central veins, pulmonary arteries and branches, chambers of the heart, larger arteries, and vascular prostheses.